This invention relates in general to battery reclaiming apparatus, and in particular to apparatus for automatically reclaiming and classifying the constituent components of whole lead-acid storage batteries.
There is a need for a relatively economical and effective way to process discarded lead-acid storage batteries so as to reclaim valuable materials remaining in those batteries. A typical storage battery removed from automotive use will contain several pounds of lead in the battery plates, the terminal posts, and interconnecting straps. A significant amount of lead oxide is also present in discarded storage batteries. Both of these materials are commercially valuable when separated from the discarded storage batteries. Discarded storage batteries provide a particularly significant source of lead; it is estimated that approximately 65% of lead production in the United States comes from secondary sources such as reclamation of storage batteries and other manufactured products containing lead.
In addition to reclaiming lead and lead oxide from storage batteries, other components of the discarded batteries may be commercially useful. Most contemporary automotive storage batteries contain cases made of plastic material, and the plastic case material (if reclaimed) can be used as a source of plastic for fabricating other molded products. The hard rubber cases used more frequently in older storage batteries may not be reusable, but must nonetheless be classified and separated from the other components of reclaimed storage batteries.
Although prior art techniques for reclaiming and classifying the components of lead-acid storage batteries have been proposed, various disadvantages are associated with these techniques. For example, some techniques utilize a chemical such as sodium carbonate in the process of reclaiming storage batteries. Another reclaiming process is incapable of processing whole storage batteries; the batteries initially must be prepared for reclamation by sawing off their tops and removing the plate groups, leaving only the tops and battery cases (including lead oxide within) to be processed. This process fails to reclaim the lead and lead oxide within the plate groups, which must be separately processed for lead reclamation. Because whole storage batteries may contain as much as eleven times more lead oxide than the battery cases and tops with plate groups removed, the inability to effectively process whole batteries is a substantial detriment.
Some techniques known in the art for separating relatively light and relatively heavy materials cannot practicably be used in reclaiming storage batteries, due to safety considerations. For example, air flow separation for use in storage battery reclamation could present a serious air pollution problem, due to the presence of lead oxide which could be entrained in the airstream.